The purpose of this three-year research project is to identify and quantify some of the potential private and social costs associated with regular marijuana use so as to enlighten the ongoing debates regarding policy reform and allocation of public funds to treatment and prevention efforts. This project will apply a methodology similar to that used by Manning et al. (1989) and Cook (1991) in their analyses of the social costs of cigarette and alcohol use. In particular, this project will evaluate the life-cycle effects of regular marijuana use on (1) educational attainment, (2) crime, and (3) health care utilization, using secondary analysis of cross-sectional, panel and time-series data sets. Data sets that will be examined include the National Longitudinal Survey of Youth, the National Education Longitudinal Survey of 1988, the Monitoring the Future Survey, the Drug Use Forecasting System, the Drug Abuse Warning Network, and the National Hospital Discharge Survey. Upon identifying the impact of marijuana use on these outcomes, the social and private nature of these costs will be evaluated. Efforts will be taken to control for concurrent use of other substances, particularly alcohol and cigarettes, so that it will be possible to identify outcomes that are clearly attributable to the consumption of marijuana. Particular questions that will be addressed by this study include the following: (1) What are the key determinants of demand for marijuana and do they change over the individual's lifetime, (2) Does regular marijuana use or abuse have a negative effect on educational attainment, (3) Does marijuana use promote criminal activity, (4) To what degree does misuse of marijuana lead to hospital emergency room episodes, and (5) Does regular marijuana use or abuse increase the cost of in-patient stays for non-marijuana related illnesses. When possible, this analysis will identify public policies that are successful at either discouraging the use of marijuana or minimizing the social cost associated with its use.